Thread tensioning device



' Oct. 19,1948.- R. N. TooNE l 2,451,889

THREAD TENsINING DEvIcE E Filed sept. 14, 1945` Patented Oct. 19, 1948'maplin 'rENsloNrNG DEVICE Ralph Norman Toone, Wollaton Park,Nottingham, England` Application September 14, 1945, Serial No. 616,229In Great Britain June 22, 1945 3 claim. (Cl. 242-149) This inventionrelates to thread tensioning devices for knitting machines and othertextile machines and has for its object to provide means whereby theapplied tension can readily be varied.

It is already known to tension a thread by passing it between twomembers the one of which rests on the other and traps the thread and itis with this type of device that the invention is concerned.

Viewed from one aspect the invention consists in the provision of meansin a device of said type whereby the rubbing area (i. e. length ofcontact). can be readily varied.' Viewed from another aspect theinvention consists in the provision of means whereby the effectiveweight on the thread can be varied. The invention further includes athread-tensioning device, comprising two superimposed members betweenwhich the thread travels to be tensioned by friction, characterised byguides affording a plurality of alternative thread paths between the twomembers to be selectively employed for varying the tension on vthethread.

The term thread is used in a generic sense and includes yarn and lamentsand wires.

The foregoing and other features set out in the appended claims areincorporated in the device which will now be described as an examplewith reference to the accompanying drawings, in which- I Figure 1 is across section through the device; Figure 2 is a perspective view of thecarrier, while Figures3 and 4 are perspective views of thel upper andlower members between which the thread is traversed and tensioned.

In one method of carrying the invention into eiect a carrier I isprovided which is trough-like or U-shape in elevation (the base of the Ubeing horizontal). and wedge or truncated U shape in plan. A seriesofeyes or slots 2 (preferably lined with porcelain or the like) isformed in each of the two converging and upstanding arms la of theU-shaped carrier so that each eye or slot of each pair is in line; aplurality of alternative thread paths of graduated lengths is therebyprovided. In the base of the carrier is iitted a wedge shaped slab 3 andabove that is iltted a similar upper slab 4; the latter slab is an easyiit and can readily rise and fall. The base of the carrier at each end.is formed with an upturned tongue Ib to inhibit movement o! the slabsin the direction of the length of the carrier. The upper slab 4 ispreferably tapered Ain elevation, being thicker at the wide end of thewedge than at the other end as shownin- Fig. 3. A thread T is passedthrough two aligned eyes or slots 2 beanother. It will be appreciatedthat the applied tension can readily be varied by the feeding of thethread through different pairs of aligned eyes or slots; vif the eyes orslots arenearer the wide part of the wedge the tension is increasedbecause the line of contact is increased and if the upper slab istapered in thickness as described the tension is further increased byreason of the increased weight.

It is found that by means of a thread tensioning device in accordancewith this invention, a constant and uniform tension can be applied to athread and the applied tension can be varied within fine limits and overa wide range in a simple and expeditious manner.

'I'he carrier l and the members 3, 4 may be made of any suitablematerial. For example the carrier may be made of porcelain or of asynthetic resin, or metal and the members 3 and 4 are preferably ofglass or other vitreous material; the meeting-edges of members 3 and 4may be chamfered and the carrier I and `members 3 and 4 may beasymmetrical in plan to ensure that members 3 and 4 can be assembledwithin the carrier only. in the one correct attitude.

I claim: v

1. A thread-tensioning device, comprising two members tapered in widthand resting one on another, and a plurality of guides providing aplurality of alternative paths for a thread between the two members,which pathsV are of differing lengths between the two members by virtueof the taper of said members.

2. A thread-tensioning device, comprising a U-shaped carrier havingconverging side walls, thread guides in said walls affording a pluralityof thread paths of diering lengths from one wall to another, and a atpressure member of tapering width between said walls for applyingprestween the slabs 3, 4 and is tensioned by the frictional contact withthe two faces of the slabs; the centre of each eye or slot ispreferablyin line with the faces of the slabs in contact with one sure to thethread in its passage.

3. A thread-tensioning device, comprising two superimposed membersbetween which the thread travels to be tensioned by friction the upperone of which members tapers in width and thickness, and guides aiordinga plurality of alternative thread paths between the two members to beselectively employed for varying the tension on the thread.

RALPH -NORMAN TOONE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,422,240 Taylor July 11, 19221,564,995 Allen Dec. 8, 1925 1.825.626 Bock Sept. 29, 1931 2,285,733Martel June 9, 1942

